Use of ct for analysis of the vertebral foramen in the hospital of querétaro / Uso de tc para análise do forame vertebral no hospital de querétaro / Uso de tc para análisis del foramen vertebral en el hospital de querétaro

ABSTRACT Objective: To determine the morphology of the vertebral foramen and its distance to the midline. Methods: Twenty cervical CT scans from the radiographic record of 12 men and 8 women, 18 to 74 years old, of C1 to C6 segments were evaluated, measuring the foramen diameter and its distance to the midline. We look for anomalies of vertebral foramen morphology, using Philips Ingenuity CT equipment with Philips IntelliSpace Portal software. Results: The mean age was 47 years; the segment with the most anomalies was C1, with 10% (increase in foramen diameter), followed by C2 and C6, with 5% (vertebral foramen hypotrophy); the mean diameter of the C1 to C6 segment was 6.081 mm, and the median distance from the midline to the vertebral foramen of C2 to C6 was 13.215 mm. The largest diameter of the vertebral foramen was C2, with a mean of 6.67 mm and the smallest was C4, with a mean of 5.75 mm; the greatest distance from the midline to the vertebral foramen was C1, with a mean of 22.59 mm and the shortest was C4, with a mean of 12.13 mm. Conclusions: The mean diameter of the vertebral foramen and its distance to the midline was determined, setting a safety region for procedures. In our city, there is no study that determines the means of the vertebral foramina diameters, the distance from the midline and its anomalies. It is necessary to rely on CT scans and to make a preoperative plan to avoid complications associated with morphological alterations.

RESUMO Objetivo: Determinar a morfologia do forame vertebral e sua distância da linha mediana. Métodos: Foram avaliadas 20 tomografias cervicais do arquivo radiográfico de 12 homens e 8 mulheres, de 18 a 74 anos de idade, dos segmentos C1 a C6, fazendo a medição do diâmetro do forame e de sua distância até a linha mediana. Buscaram-se as anomalias da morfologia do forame vertebral, usando um equipamento Philips Ingenuity CT com o software Philips IntelliSpace Portal. Resultados: A média de idade foi 47 anos; o segmento com mais anomalias foi C1, com 10% (aumento do diâmetro do forame), seguido por C2 e C6, com 5% (hipotrofia do forame vertebral); o diâmetro médio do segmento C1 a C6 foi 6,081 mm e a distância média da linha mediana até o forame vertebral de C2 a C6 foi 13,215 mm. O maior diâmetro do forame vertebral foi C2, com média de 6,67 mm e o menor foi C4, com média de 5,75 mm; a maior distância da linha mediana até o forame vertebral foi a de C1, com média de 22,59 mm e a menor foi em C4, com média de 12,13 mm. Conclusões: Foi determinada a média do diâmetro do forame vertebral e sua distância até a linha mediana, estabelecendo-se uma região de segurança para procedimentos. Em nossa cidade, não há um estudo que determine a médias dos diâmetros do forame vertebral, a distância da linha mediana e suas anomalias. É preciso contar com a tomografia e fazer um plano pré-operatório para evitar as complicações associadas às alterações morfológicas.

RESUMEN Objetivo: Determinar la morfología del foramen vertebral y su distancia de la línea media. Métodos: Se evaluaron 20 tomografías cervicales, del archivo radiográfico de 12 hombres y 8 mujeres, de 18 a 74 años de edad, del segmento C1 a C6, realizando la medición del diámetro del foramen, y su distancia de la línea media. Se buscaron las anomalías morfológicas del foramen vertebral, usando un equipo Philips Ingenuity CT y software Philips IntelliSpace Portal. Resultados: La edad promedio fue de 47 años; el segmento con más anomalías fue C1, con 10% (aumento del diámetro del foramen), seguido de C2 y C6 con 5% (hipotrofia del foramen vertebral); el promedio del diámetro del segmento C1 a C6 fue de 6,081 mm y el promedio de distancia de la línea media al foramen vertebral de C2 a C6 fue 13,215 mm. El mayor diámetro del foramen vertebral fue en C2, con promedio de 6,67 mm y el menor fue en C4 con promedio de 5,75 mm; la mayor distancia de línea media al foramen vertebral correspondió en C1 con promedio de 22,59 mm y la menor fue en C4 con promedio de 12,13 mm. Conclusiones: Se determinó el promedio del diámetro del foramen vertebral y su distancia a la línea media, estableciendo una zona de seguridad para procedimientos. En nuestra ciudad no existe un estudio que determine promedios del diámetro del foramen vertebral, la distancia desde la línea media y sus anomalías. Es preciso contar con tomografía y hacer un plan preoperatorio para evitar las complicaciones asociadas con alteraciones morfológicas.

Estudo anatômico da relação do gânglio da raiz dorsal com o disco intervertebral na coluna lombar / Anatomical study on the relationship between the dorsal root ganglion and the intervertebral disc in the lumbar spine

Descrever a localização do gânglio da raiz dorsal em relação ao disco intervertebral, incluindo a zona "triangular"de segurança para cirurgia minimamente invasiva na coluna lombar. MÉTODOS: Oito cadáveres adultos foram dissecados bilateralmente, na região lombar, com a abordagem posterolateral, até exposição dos espaços L3L4 e L4L5 e se obtiveram medidas referentes ao espaço entre o disco intervertebral, os pedículos cranial e caudal ao disco, o trajeto da raiz nervosa, o gânglio dorsal e o triângulo de segurança. RESULTADOS: As medidas obtidas foram constantes, sem diferenças significativas entre níveis ou lateralidade. O gânglio dorsal ocupou a borda lateral da zona triangular de segurança em todos os espécimes analisados. CONCLUSÃO: A localização precisa do gânglio mostra que a margem de segurança para procedimentos minimamente invasivos é menor do que a apresentada nos estudos que envolvem apenas medidas da raiz nervosa, o que explica talvez a presença de dor neuropática após alguns desses procedimentos.

To describe the location of the dorsal root ganglion in relation to the intervertebral disc, including the "triangular" safety zone for minimally invasive surgery in the lumbar spine. METHODS: Eight adult cadavers were dissected bilaterally in the lumbar region, using a posterolateral approach, so as to expose the L3L4 and L4L5 spaces, thereby obtaining measurements relating to the space between the intervertebral disc, pedicles cranial and caudal to the disc, path of the nerve root, dorsal ganglion and safety triangle. RESULTS: The measurements obtained were constant, without significant differences between levels or any laterality. The dorsal ganglion occupied the lateral border of the triangular safety zone in all the specimens analyzed. CONCLUSION: Precise localization of the ganglion shows that the safety margin for minimally invasive procedures is less than what is presented in studies that only involve measurements of the nerve root, thus perhaps explaining the presence of neuropathic pain after some of these procedures.

Morphometrical dimensions of the sheep thoracolumbar vertebrae as seen on digitised CT images / 한국실험동물학회지

The sheep spine is widely used as a model for preclinical research in human medicine to test new spinal implants and surgical procedures. Therefore, precise morphometric data are needed. The present study aimed to provide computed tomographic (CT) morphometry of sheep thoracolumbar spine. Five adult normal Merino sheep were included in this study. Sheep were anaesthetised and positioned in sternal recumbency. Subsequently, transverse and sagittal images were obtained using a multi-detector-row helical CT scanner. Measurements of the vertebral bodies, pedicles, intervertebral disc and transverse processes were performed with dedicated software. Vertebral bodies and the spinal canal were wider than they were deep, most obviously in the lumbar vertebrae. The intervertebral discs were as much as 57.4% thicker in the lumbar than in the thoracic spine. The pedicles were higher and longer than they were wide over the entire thoracolumbar spine. In conclusion, the generated data can serve as a CT reference for the ovine thoracolumbar spine and may be helpful in using sheep spine as a model for human spinal research.

Quantitative Morphologic Assessment of Thoracolumbar Vertebrae in Korean Women by Morphometric X-rayAbsorptiometry

PURPOSE: To compare the accuracy of lateral radiography of the spine with that of morphometric X-rayabsorptiometry(MXA) in vertebral morphometry, and to evaluate normal vertebral morphometry using MXA in Koreanwomen. MATERIALS AND METHODS: A spine phantom was constructed using copper pipe. Its anterior and posteriorheights were measured directly, with lateral radiographs and with MXA, and the values thus obtained were compared.Inter -and intra -observer variations were evaluated by three radiologists. The vertebral morphometry of 30 youngwomen volunteers were imaged using thoracic and lumbar lateral radiographs and MXA, and analysis included themeasurement of anterior and posterior heights from T4 to L4. We also obtained the vertebral morphometry of 200normal Korean women who underwent MXA between March 1995 and February 1996, though those with osteoporosis andother spinal lesions were excluded from this study. Thoracolumbar vertebral indexes were statistically correlatedwith age, height and bone mineral. RESULTS: There were no statistically significant differences in the heights ofspine phantom measured by MXA compared with actual size (mean difference=0.28mm). Simple radiographs weremagnified by 23.7% at a phantom-table distance of 15cm, and distortion ranged from 0.5% to 22.5%, depending onphantom level and phantom-table distance. In the study of volunteers, the magnification rate between a simpleradiograph and MXA was about 26.6%. Anterior height increased progressively from the thoracic to the lumbar spine,though posterior height peaked at L2, and L4 was less than anterior height. In Korean women, indices of vertebralmorphometry decreased significantly with aging, with the most prominent decrease occurring during the seventhdecade. The mineral density of spinal bone decreased markedly after the sixth decade. CONCLUSION: Radiographsshowed more magnification and distortion than did MXA, though between morphometric X-ray absorptiometry (MXA) andactual size, there was no significant difference. The vertebral morphometric indices of Korean women and referredbone mineral density may provide useful data for determining and evaluating follow-up changes in spinalmorphology.

Normal Variation of Lumbosacral Thecal Sac on MR

PURPOSE: To evaluate the shape and distal end level of the lumbosacral the cal sac in normal subjects on MR imaging. MATERIALS AND METHODS: One hundred and twelve normal lumbar MRIs were reviewed. The shape and distal endlevel of the lumbosacral thecal sac on T1-weighted midine sagittal image were evaluated. The thecal sac was divided into five types, according to shape and defined as follows : type I(pointed shape) : tapering contour, with rat tail appearance ; type II(ovoid shape) : tapering smoothly, with round end ; type III(round shape) : not tapering, with round end ; type IV(pointed ovoid shape) : ending in papilae ; type V(round pointed shape) : ending in papillae. The levels of the distal end of the thecal sac were also evaluated. RESULTS: Type I was the mostcommon(43/112, 38/4%) and the second most common form was type II(31/112, 27.7%). With regard to the distal end level of the sac, 33 cases were located at the distal one third of the S2 body and 28 were at the middle one third; 16 cases were at the distal one third of the S1 body, and 14 were at the S1-S2 intervertebral disc level. All lumbosacral thecal sacs terminated between the L5-S1 intervertebral body and the distal one third of the S3 body. CONCLUSION: Lumbosacral thecal sacs ended between the L5-S1 intervertebral disc and the S3 spinal body. Most commonly, the sac terminated at the proximal one third of the S2 body. The pointed shape(type I) was most common.